Nonhygroscopic single crystals of beta -Zn3BPO7 have been grown from the st
oichiometric melt and characterized as a nonlinear optical crystal. The pha
se transition of beta -Zn3BPO7 into alpha -Zn3BPO7 is effectively suppresse
d by the appropriate heat treatment. This crystal is transparent down to 25
0 nm, and its nonlinear coefficient d(11) = 0.69 pm/V. (C) 2001 Elsevier Sc
ience B.V. All rights reserved.